Hermetic compressor

ABSTRACT

A hermetic compressor to conduct electricity to a stator coil without peeling off a coating formed on the coil while preventing the separation of the stator coil or lead wire from a compressible terminal. In the hermetic compressor including a hermetic container, a compression device to compress a refrigerant, a drive device to drive the compression device, the drive device including a stator formed by winding the stator coil on a core and a rotor to rotate inside the stator, the lead wire extending from a terminal block to receive electricity, and a compressible terminal to be compressed after the stator coil and the lead wire are inserted into the compressible terminal, the stator coil is formed by covering an aluminum wire with an enamel coating, and the compressible terminal includes electricity-conduction protrusions to piece the enamel coating so as to come into contact with the aluminum wire.

TECHNICAL FIELD

The present invention relates to a hermetic compressor, and, more particularly, to a hermetic compressor in which a stator coil of a stator and a lead wire of a terminal block are connected to each other by use of a compressible terminal.

BACKGROUND ART

In general, a hermetic compressor includes a hermetic container having a hermetic space therein, and a compression device to compress a refrigerant and a drive device to drive the compression device, which are mounted in the hermetic container.

Specifically, the drive device to provide the compression device with a drive force includes a stator fixed in the hermetic container and a rotor installed inside the stator with a gap therebetween to electromagnetically interact with the stator, the overall drive device acting as a single motor.

The stator of the drive device is formed by winding a plurality of stator coils on a core. The stator coils are connected to a plurality of lead wires extending from a terminal block, and the terminal block is coupled with a terminal provided in the hermetic container for the supply of electricity. Each stator coil is formed by covering a solid copper wire with an enamel coating, to prevent a short-circuit with another stator coil in use.

To connect the stator coils, wound on the core, to the lead wires extending from the terminal block, respectively, ends of the stator coils and ends of the lead wires are connected to each other by use of compressible terminals.

Specifically, to send electricity to the stator coils by connecting the ends of the stator coils to the ends of the lead wires, first, the enamel coating of each stator coil is peeled off to expose the copper wire, and thereafter, the exposed copper wire having no enamel coating is connected to the end of the corresponding lead wire by use of the compressible terminal.

Peeling off the enamel coating from the respective stator coils for the connection of the lead wires and the conduction of electricity, however, is very troublesome work.

Moreover, if a tensile force is applied to the stator coils or the lead wires after the stator coils are connected to the lead wires by use of the compressible terminals, there is a problem in that the stator coils or the lead wires are easily separated from the compressible terminals.

DISCLOSURE OF INVENTION Technical Problem

Therefore, the present invention has been made in order to solve the above problems, and it is an aspect of the invention to provide a hermetic compressor, which can send electricity to a stator coil without peeling off a coating formed on the stator coil.

It is another aspect of the invention to provide a hermetic compressor, which can prevent a stator coil or a lead wire from being separated from a compressible terminal even if a tensile force is applied after the stator coil and the lead wire are connected to each other by the compressible terminal.

Technical Solution

In accordance with one aspect, the present invention provides a hermetic compressor comprising: a hermetic container; a compression device to compress a refrigerant; a drive device to drive the compression device, the drive device including a stator formed by winding a stator coil on a core and a rotor to rotate inside the stator; a lead wire extending from a terminal block, coupled to a terminal installed in the hermetic container, to receive electricity; and a compressible terminal to be compressed in a state in which the stator coil and the lead wire are inserted into the compressible terminal to connect the stator coil and the lead wire to each other, wherein the stator coil is formed by covering an aluminum wire with an enamel coating, and the compressible terminal includes at least one electricity-conduction protrusion to piece the enamel coating so as to come into contact with the aluminum wire for the conduction of electricity trough the stator coil.

The at least one electricity-conduction protrusion may include a plurality of electricity-conduction protrusions formed in a circumferential direction of the compressible terminal.

V alleys may be formed between the respective neighboring electricity-conduction protrusions, to allow the enamel coating to be partially inserted into the valleys.

Each of the electricity-conduction protrusions may have a triangular cross section.

The compressible terminal may further include at least one anti-separation protrusion to press the lead wire for preventing the lead wire from being separated from the compressible terminal.

The at least one anti-separation protrusion may include a plurality of anti-separation protrusions formed in a circumferential direction of the compressible terminal.

Inserting grooves may be formed between the respective neighboring anti-separation protrusions, to allow the lead wire to be partially inserted into the inserting grooves when the compressible terminal is compressed.

Each of the anti-separation protrusions may have a square cross section.

The compressible terminal may be a conductor to conduct electricity therethrough.

In accordance with another aspect, the present invention provides a hermetic compressor comprising: a hermetic container; a compression device to compress a refrigerant; a drive device including a stator and a rotor to drive the compression device; a stator coil to apply electricity to the stator; a lead wire extending from a terminal block, coupled to a terminal installed in the hermetic container, to receive electricity; and a compressible terminal to be compressed in a state in which the stator coil and the lead wire are inserted therein to connect the stator coil and the lead wire to each other, wherein the compressible terminal includes a plurality of electricity-conduction protrusions to conduct electricity to the stator coil even if the compressible terminal is compressed in a state in which the stator coil is inserted into the compressible terminal without undergoing a peeling operation.

The stator coil may be formed by covering an aluminum wire with an enamel coating.

The compressible terminal may further include: a plurality of anti-separation protrusions to compress the lead wire for preventing the lead wire from being separated from the compressible terminal; and inserting grooves formed between the respective neighboring anti-separation protrusions to allow the lead wire to be partially inserted into the inserting grooves.

Advantageous Effects

The present invention provides a hermetic compressor having the following effects.

Firstly, the present invention can achieve a simplified electrically-conductive connection between a stator coil and a lead wire via a compressible terminal without peeling off a coating formed on the stator coil.

Secondly, the present invention can prevent a breakage of the stator coil made of an aluminum wire having a low tensile strength because the enamel coating surrounds the aluminum wire to reinforce the tensile strength of the aluminum wire.

Thirdly, the present invention can prevent the stator coil or the lead wire from being separated from the compressible terminal even if a tensile force is applied to the stator coil or the lead wire.

DESCRIPTION OF DRAWINGS

The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a sectional view of a hermetic compressor according to an embodiment of the present invention;

FIG. 2 is a perspective view illustrating the connection of stator coils from a stator and lead wires from a terminal block, included in the hermetic compressor shown in FIG. 1;

FIG. 3 is a partial cut-away perspective view illustrating a compressible terminal to connect the stator coil and the lead wire to each other; and

FIG. 4 is a sectional view illustrating the stator coil and the lead wire connected to each other by the compressible terminal.

BEST MODE

Reference will now be made in detail to a hermetic compressor according to a preferred embodiment of the present invention. The embodiment is described below to explain the present invention by referring to the figures.

The hermetic compressor according to the embodiment of the present invention, as shown in FIG. 1, includes a hermetic container 10, and a compression device 20 to compress a refrigerant and a drive device 30 to drive the compression device 20, which are mounted in the hermetic container 10.

The compression device 20 includes a cylinder block 22 integrally formed with a frame 21 and forming a compression chamber 22 a therein, a piston 23 to move forward and rearward in the compression chamber 22 a so as to compress a refrigerant, a cylinder head 24 coupled to a side of the cylinder block 22 and having a suction chamber 24 a and a discharge chamber 24 b, which communicate with the outside, and a valve unit 25 interposed between the cylinder block 22 and the cylinder head 24 to control the inflow and outflow of the refrigerant.

The drive device 30 moves the piston 23 forward and rearward to compress the refrigerant in the compression device 20. The drive device 30 includes a stator 31 to create a magnetic field, a rotor 32 installed inside the stator 31 with a gap therebetween to electromagnetically interact with the stator 31, and a rotating shaft 33 press-fitted in the center of the rotor 32 to rotate together with the rotor 32.

The rotating shaft 33 rotates in the frame 21, and an upper end of the rotating shaft 33 forms an eccentric portion 33 a to perform an eccentric rotation. A connecting rod 26 is installed between the eccentric portion 33 a and the piston 23 to convert the eccentric rotation of the eccentric portion 33 a to a linear reciprocating movement of the piston 23.

If electricity is applied to the hermetic compressor having the above described configuration, the stator 31 creates a magnetic field to rotate the rotor 32 that electromagnetically interacts with the stator 31. Simultaneously with the rotation of the rotor 32, the rotating shaft 33 is rotated. In turn, the rotation of the rotating shaft 33 is converted to a linear reciprocating movement of the piston 23 by the connecting rod 26 connected to the eccentric portion 33 a formed at the upper end of the rotating shaft 33. Thereby, the piston 23 compresses the interior of the compression chamber 22 a.

Meanwhile, to supply electricity to the stator 31, the hermetic container 10 receives a terminal 40 therein, and a terminal block 41 is connected to the terminal 40 while being received in the hermetic container 10.

The stator 31 of the drive device 30, as shown in FIG. 2, includes a core 31 a and a plurality of stator coils 31 b wound on the core 31 a. Each stator coil 31 b is formed by covering an aluminum wire 35 with an enamel coating 36. Since an aluminum wire has a price a third of that of a copper wire, the stator coils 31 b made of aluminum wires can achieve a reduction in the manufacturing costs of the hermetic compressor.

Meanwhile, a plurality of lead wires 42 extend from one end of the terminal block 41 coupled to the terminal 40. Each lead wire 42 is formed by covering a copper wire 43 with a coating member 44. The copper wire 43 is a stranded wire formed by stranding a plurality of slender copper wires.

To apply electricity to the stator 31, ends of the plurality of stator coils 31 b of the stator 31 are connected, respectively, to ends of the plurality of lead wires 42 extending from the terminal block 41, to form junctions 60.

In the formation of the junctions 60 to apply electricity to the stator 31, prior to connecting the lead wires 42 and the stator coils 31 b to each other, the enamel coating 36 has to be peeled off from an end of each stator coil 31 b to expose the aluminum wire 35, and the coating member 44 has to be peeled off from an end of each lead wire 42 to expose the copper wire 43.

However, the copper wire has a tensile strength of 22 kg/mm² at a room temperature, whereas the aluminum wire has a tensile strength of 10 kg/mm². Therefore, when a tensile force is applied to the stator coil 31 b from which the enamel coating 36 was peeled off, it may cause a breakage of the aluminum wire 35 having the low tensile strength.

Therefore, in the case where the aluminum wire 35 is used to constitute the stator coil 31 b, it is preferable to conduct electricity to the stator coil 31 b without peeling off the enamel coating 36 from the aluminum wire 35.

FIG. 3 illustrates a compressible terminal 50 to achieve the conduction of electricity to the stator coil 31 b without peeling off the enamel coating 36 from the aluminum wire 35.

As shown in FIG. 3, the compressible terminal 50, to connect the stator coil 31 b and the lead wire 42 to each other, is a conductor to conduct electricity therethrough. The compressible terminal 50 has a partially cut-away cylinder shape, and includes a first insertion portion 51 for the insertion of the stator coil 31 b and a second insertion portion 55 for the insertion of the lead wire 42.

After the stator coil 31 b is inserted into the first insertion portion 51 and the lead wire 42 is inserted into the second insertion portion 55, the compressible terminal 50 is compressed by use of a compressing machine (not shown). As the compressible terminal 50 is compressed, the diameter of the compressible terminal 50 decreases, thereby causing both ends of the compressible terminal 50, which are originally spaced apart from each other, to come into contact with each other. In this way, the compressible terminal 50 forms the junction 60 to connect the end of the stator coil 31 b and the end of the lead wire 42 to each other.

Meanwhile, according to the present invention, in the course of inserting the stator coil 31 b into the first insertion portion 51, it is unnecessary to peel off the enamel coating 36 formed on the stator coil 31 b. This is because the first insertion portion 51 is internally formed with electricity-conduction protrusions 52. The electricity-conduction protrusions 52 pierce the enamel coating 36 of the stator coil 31 b when the compressible terminal 50 is compressed, so as to come into contact with the aluminum wire 35 surrounded by the enamel coating 36.

The plurality of electricity-conduction protrusions 52 are arranged in a circumferential direction of the compressible terminal 50, and a plurality of valleys 53 are also formed in the circumferential direction of the compressible terminal 50 between the respective protrusions 52.

Each of the electricity-conduction protrusions 52 has a sharp end suitable to pierce the enamel coating 36 when the compressible terminal 50 is compressed in a state wherein the stator coil 31 b is inserted into the first insertion portion 51 of the compressible terminal 50. In the present embodiment, each electricity-conduction protrusion 52 has a triangular cross section, to enable an end 52 a of the electricity-conduction protrusion 52 to pierce the enamel coating 36 of the stator coil 31 b.

The second insertion portion 55, for the insertion of the lead wire 42, is internally formed with anti-separation protrusions 56 and inserting grooves 57 to prevent the lead wire 42 from being separated from the compressible terminal 50. The plurality of anti-separation protrusions 56 are formed in the circumferential direction of the compressible terminal 50, and the plurality of inserting grooves 57 are also formed in the circumferential direction of the compressible terminal 50 between the respective anti-separation protrusions 56.

Each of the anti-separation protrusions 56 preferably has a square cross section to press the copper wire 43 when the compressible terminal 50 is compressed in a state wherein the lead wire 42 is inserted into the second insertion portion 51 of the compressible terminal 50.

FIG. 4 is a sectional view illustrating a state wherein the stator coil 31 b and the lead wire 42 are compressed and connected to each other by the compressible terminal 50.

As shown in FIG. 4, after inserting the stator coil 31 b into the first insertion portion 51 and the lead wire 42 into the second insertion portion 52, the compressible terminal 50 is compressed by a not shown compressing machine.

When the compressible terminal 50 is compressed, the electricity-conduction protrusions 52 pierce the enamel coating 36 of the stator coil 31 b to come into contact with the aluminum wire 35. In addition, since the compressible terminal 50 is a conductor, electricity can be conducted to the stator coil 31 b without peeling off the enamel coating 36. Furthermore, since the electricity-conduction protrusions 52 are fitted into the enamel coating 36, and the enamel coating 36 is partially inserted into the valleys 53 between the electricity-conduction protrusions 52, there is no risk that the stator coil 31 b is separated from the compressible terminal 50 even if a tensile force is applied to the stator coil 31 b.

In the present invention, since the stator coil 31 b is inserted into the compressible terminal 50 without peeling off the enamel coating 36, the enamel coating 36 acts to reinforce the tensile strength of the aluminum wire 35. This has the effect of preventing a breakage of the stator coil 31 b even if a tensile force is applied to the stator coil 31 b.

In relation to the lead wire 42 having the copper wire 43 that is a stranded wire formed by stranding a plurality of slender copper wires, when the compressible terminal 50 is compressed after the lead wire 42 is inserted into the second insertion portion 22, the anti-separation protrusions 56 press the copper wire 43 with a strong pressure, and a part of the copper wire 43, which is relatively not pressed by the anti-separation protrusions 56, is inserted into and caught by the inserting grooves 57. As a result that the copper wire 43 is pressed by the anti-separation protrusions 56 while being partially inserted into and caught by the inserting grooves 57, the present invention has the effect of preventing the lead wire 42 from being separated from the compressible terminal 50 even if a tensile force is applied to the lead wire 42.

It will be appreciated that the hermetic compressor according to the embodiment of the present invention is described above, but the present invention is not limited thereto, and includes all equivalents thereof.

Mode for Invention

As apparent from the above description, a hermetic compressor according to the present invention has the following effects.

Firstly, according to the present invention, a stator coil can be connected to a lead wire for the conduction of electricity as it is inserted into a compressible terminal without peeling off a coating formed thereon. This enables a simplified connection between the stator coil and the lead wire.

Secondly, even when the stator coil is made of an aluminum wire having a low tensile strength, the stator coil has no risk of a breakage of the aluminum wire because the aluminum wire is surrounded by an enamel coating to reinforce the tensile strength of the aluminum wire.

Thirdly, even if a tensile force is applied to the stator coil or the lead wire, it is possible to prevent the stator coil or the lead wire from being separated from the compressible terminal.

Although embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents. 

1. A hermetic compressor comprising; a hermetic container; a compression device to compress a refrigerant; a drive device to drive the compression device, the drive device including a stator formed by winding a stator coil on a core and a rotor to rotate inside the stator; a lead wire extending from a terminal block, coupled to a terminal installed in the hermetic container, to receive electricity; and a compressible terminal to be compressed in a state in which the stator coil and the lead wire are inserted into the compressible terminal to connect the stator coil and the lead wire to each other, wherein the stator coil is formed by covering an aluminum wire with an enamel coating, and the compressible terminal includes at least one electricity-conduction protrusion to piece the enamel coating so as to come into contact with the aluminum wire for the conduction of electricity trough the stator coil.
 2. The hermetic compressor according to claim 1, wherein the at least one electricity-conduction protrusion includes a plurality of electricity-conduction protrusions formed in a circumferential direction of the compressible terminal.
 3. The hermetic compressor according to claim 2, wherein valleys are formed between the respective neighboring electricity-conduction protrusions, to allow the enamel coating to be partially inserted into the valleys.
 4. The hermetic compressor according to claim 2, wherein each of the electricity-conduction protrusions has a triangular cross section.
 5. The hermetic compressor according to claim 1, wherein the compressible terminal further includes at least one anti-separation protrusion to press the lead wire for preventing the lead wire from being separated from the compressible terminal.
 6. The hermetic compressor according to claim 5, wherein the at least one anti-separation protrusion includes a plurality of anti-separation protrusions formed in a circumferential direction of the compressible terminal.
 7. The hermetic compressor according to claim 6, wherein inserting grooves are formed between the respective neighboring anti-separation protrusions, to allow the lead wire to be partially inserted into the inserting grooves when the compressible terminal is compressed.
 8. The hermetic compressor according to claim 5, wherein each of the anti-separation protrusions has a square cross section.
 9. The hermetic compressor according to claim 1, wherein the compressible terminal is a conductor to conduct electricity therethrough.
 10. A hermetic compressor comprising: a hermetic container; a compression device to compress a refrigerant; a drive device including a stator and a rotor to drive the compression device; a stator coil to apply electricity to the stator; a lead wire extending from a terminal block, coupled to a terminal installed in the hermetic container, to receive electricity; and a compressible terminal to be compressed in a state in which the stator coil and the lead wire are inserted therein to connect the stator coil and the lead wire to each other, wherein the compressible terminal includes a plurality of electricity-conduction protrusions to conduct electricity to the stator coil even if the compressible terminal is compressed in a state in which the stator coil is inserted into the compressible terminal without undergoing a peeling operation.
 11. The hermetic compressor according to claim 10, wherein the stator coil is formed by covering an aluminum wire with an enamel coating.
 12. The hermetic compressor according to claim 10, wherein the compressible terminal further includes: a plurality of anti-separation protrusions to compress the lead wire for preventing the lead wire from being separated from the compressible terminal; and inserting grooves formed between the respective neighboring anti-separation protrusions to allow the lead wire to be partially inserted into the inserting grooves. 